The unfounded claim came after Unsworth called Musk's miniature sub a "PR stunt."

(CNN) -- British rescuer Vern Unsworth says he is considering legal action against US billionaire Elon Musk after he made an unfounded and disparaging claim he was a "pedo", or pedophile, in a now-deleted tweet.

Unsworth, a caver based in Thailand, provided knowledge of the Tham Luang cave system, which helped with the rescue of 12 school boys and their soccer coach in a flooded Thai cave last week.

Musk, the CEO of several high-profile American tech companies, broadcast the claim to his 22 million social media followers on Sunday after Unsworth criticized a miniature submarine he made.

Asked by a Nine Network reporter if he was going to take legal action again Musk, Unsworth replied: "Yes, yes, it's not finished."

"I believe he's called me a pedophile. Well, (if) by definition rescuing 12 young boys...that puts everybody in the same context."

Asked how he felt about Musk's remark, Unsworth added: "I am not gonna make any further comment about him but I think people realize what sort of a guy he is."

The unfounded claim came after Unsworth called Musk's miniature sub a "PR stunt."

He had said in an earlier interview with CNN that Musk's miniature escape pod "had absolutely no chance of working."

He can "stick his submarine where it hurts," Unsworth said during the interview in Thailand.

Musk posted the baseless accusation shortly after. There is no indication that Musk's statement is true and he provided no justification or proof to back up his claim.

When Twitter users called out Musk's attack on Unsworth as unfair, he doubled down.

"Bet ya a signed dollar it's true," he wrote in another tweet that has since been removed.

Representatives for Musk and his companies — SpaceX, Boring Co. and Tesla — did not respond to requests for comment Sunday.

In the midst of the tense rescue mission earlier this month, Musk announced plans to help. He proceeded to post regular updates on social media, including photos and a video of a "kid-size" submarine being constructed and tested.

Ultimately, the capsule was not used in the rescue mission, and it was criticized by some as a distraction. The mission commander, Narongsak Osotthanakorn, said at one point that the submarine "doesn't fit with our mission," according to the BBC.

Unsworth's comments came as it was reported that two Australians who assisted in the international effort to help the Thai football team were given diplomatic immunity in case anything went wrong during the rescue.

According to broadcaster ABC, Dr Craig Challen and Dr Richard Harris were given diplomatic immunity ahead of the risky mission, after negotiations between Australian and Thai Government officials.

Challen has explained how he worked closely with Harris to medically assess the boys and their coach and get them ready for the rescue operation. Challen confirmed that the boys were heavily sedated to make the rescue possible.